Opponents of the deal will spend millions of dollars on ads pushing the U.S. public and Congress to kill the deal in the next few days. But while a fortune already has been spent on nit-picking the ongoing talks, virtually nothing has been invested in developing an alternative, viable solution to limit Iran's nuclear activities.

The reality is that the opponents of the deal don't have a solution, they only have criticism. And for many, the real value of the nuclear deal has been lost amid the barrage of condemnation surrounding the talks.

It's worthwhile to remind ourselves why this deal is so important -- and why it would be a strategic mistake of Iraq War proportions to let this opportunity slip out of our hands.

Trita Parsi

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Preventing the bomb ...

The two first objectives the deal would achieve are paramount: firstly, it will prevent an Iranian nuclear bomb; secondly, it will prevent a disastrous war with Iran.

The limitations and inspections regime the deal would impose on the Iranian nuclear program will make it virtually impossible for Tehran to build a bomb. Were it to choose to go down that path, it would get caught almost instantaneously thanks to the new high-tech inspection instruments that will be installed at Iranian nuclear facilities.

In addition, if evidence arises that Iran has begun nuclear activities at undeclared sites, then Iran will be obliged to provide access to those sites as well.

No other option comes even close to this deal when it comes to closing off all of Iran's paths to a bomb. Military action in particular is far inferior -- and far more risky.

If the talks fail -- or are undermined -- Iran's nuclear program would unshackle, enabling Tehran to inch closer to a weapons option. That in turn, would increase the risk of an Israeli or American attack on Iranian targets, even though bombing the country's nuclear facilities would at best only slow the program a few years.

The Iranians would hit back and soon enough, and the U.S. would be embroiled in yet another war in the Middle East with no end in sight. No wonder the Iran deal has broad support among the U.S. public.

This is particularly important at a time when the violent winds of religious radicalism are ravaging the Middle East and beyond. America is in desperate need of an injection of political moderation in the region. An Iran that moves towards democracy could provide that.

A boost in the fight against ISIS

Fourth, ISIS and other jihadist groups threaten both Iran and the U.S. Yet coordination and collaboration between the two against these violent terrorist organizations has been minimal because neither side has the political ability to expand coordination until the nuclear dispute has been settled first.

A well-placed Iranian source told me recently that in a post-deal environment, Iran is ready to put in 40,000-60,000 ground troops to eliminate ISIS over the next three years. Ideally, the U.S. would provide air support, he explained. The source made clear the commitment would not be a quid pro quo to get a nuclear deal.

There is near-consensus that airstrikes alone will not defeat ISIS. Ground troops are needed, but who will provide them? The American public is certainly not in the mood for putting more troops on the ground in Iraq. The Iraqi army has proven desperately inadequate. The nuclear deal may help square this circle.

Deal gives America more options

Last but not least, the nuclear deal can help provide America with more options in the region in the sense that it reduces America's reliance on authoritarian Arab states such as Saudi Arabia -- which, despite being a key U.S. ally, has played a central role in spreading Islamic radicalism and jihadism.

As Jeremy Shapiro and Richard Sokolsky recently pointed out, the Iran deal is not about getting into bed with Tehran. But it can be used to get out of bed with the Saudis. And with that, America's hands will be freer to truly deal with and defeat the threat of Islamic radicalism fomented by the Salafists in the Saudi kingdom.

Former Chairman of the Joint Chiefs of Staff Admiral Mike Mullen put it best: "We need to re-examine all of the relationships we enjoy in the region, relationships primarily with Sunni-dominated nations. Detente with Iran might better balance our efforts across the sectarian divide."

In the coming weeks, emotions will run high in the debate over the Iran deal. It will be critical to distinguish between the minutia and the truly essential. At historic moments like this, it is the bigger picture that counts.